The sentence without any commas best communicates that the koala is eating multiple items, rather than engaging in multiple actions. This is a classic example of how an understanding of grammar can keep the meaning of a sentence from spiraling out of control. Lynne Truss’ book, “Eats, Shoots & Leaves,” contains many more misplaced comma gems.

Which sentence is grammatically correct?

She believes in the existence of UFOs but doesn’t believe in Santa Claus.

She believes in the existence of UFOs, but doesn’t believe in Santa Claus

She believes in the existence of UFOs but, doesn’t believe in Santa Claus

She believes in the existence of UFOs; but doesn’t believe in Santa Claus.

Since this sentence only has one independent clause, it doesn’t require a comma before the conjunction “but.” All good grammar nerds know that you only need a comma before a conjunction if you are separating two independent clauses.

What is an appositive?

A punctuation mark that shows possession

A noun or a noun phrase that gives more information about the noun that precedes it

A verb phrase

A word or phrase that indicates a transition

An appositive, a grammatical term not many people are familiar with, is a noun or a noun phrase that provides more information about the noun just before it. The word is the adjectival form of “apposition,” which means being positioned side by side.

Why is parallel structure important to maintain?

It juxtaposes different sounds and ideas for rhetorical effect.

It cues readers to know what is going to happen next.

It helps organize paragraphs by providing transitional markers.

It shows that the items in a list are of equal importance and helps readability.

Parallel structure requires writers to use the same form of words, phrases, or clauses for items in a list. This parallel use of forms shows that the items listed are of equal importance. For example, he enjoys brushing his teeth, riding his bike, and washing his spinach.

Which of the following is a fragment?

I’d like to go.

Like to what?

I’d like to go to a swimming hole.

However, they are all Infested with alligators.

​“Like to what?” is a fragment here, as are many of the constructions we use in ordinary conversation. A fragment is an incomplete sentence because it does not have a subject and a verb and compose a complete thought. Fragments are totally acceptable in casual conversation but they are unacceptable in formal writing.

Which sentence has a dangling modifier?

Having completed his homework, Joe went straight to the game.

Having completed his homework, the game began.

Having completed his homework Joe went straight to the game.

Having completed his homework, Joe made a plate of nachos.

In the sentence “Having completed his homework, the game began,” “having completed his homework” is a dangling modifier. The noun that this participle modifies is nowhere to be found. We’re left just dangling here wondering who completed his homework. It’s not cool to leave your friends dangling.

Which sentence is punctuated correctly?

My daughter, Adelaide, refuses to wear her helmet while going down the slide.

My daughter Adelaide refuses to wear her helmet, while going down the slide.

My daughter Adelaide, refuses to wear her helmet while going down the slide.

My daughter Adelaide refuses to wear her helmet while going down the slide.

This sentence is an example of an appositive that is restrictive for the sentence, so it does not need commas to set apart the name Adelaide. More often, appositives are non-restrictive, meaning that the sentence does not rely on them to convey its message. When the meaning is not essential to the sentence, appositives are set apart with commas.

What is a gerund?

A verb ending in -ing

A verb phrase

A verbal that ends in -ing and acts as a noun

A noun that modifies what came before it

Gerund is one of those grammar words that most of us have heard, but few of us know the meaning of. Gerunds are verbals—derived from a verb but not acting as a verb—which end in -ing and act as a noun. For example, in the sentence “Knowing all about grammar always helped her make friends with the cool kids,” “knowing all about grammar” is the gerund phrase, with “knowing” is the gerund.

Which word is the direct object of this sentence? She threw a lot of sass in his direction.

Direction

A lot

Sass

His

The direct object answers the question, "She threw what?" In this case, she threw sass. Not all verbs require a direct object. But for those that do, the sentence becomes incomplete without it. The sentence “She threw” is not a complete thought because we’re left wondering what she threw. Sass, that’s what.

Which sentence correctly uses parallel structure?

When I get old, I’m going to water my plants, do yoga, and ride dirt bikes.

When I get old, I’m going to water my plants, do yoga, and riding dirt bikes.

When I get old, I’m going to water my plants, doing yoga and riding dirt bikes.

When I get old, I’m going to water my plants, to do yoga, and ride dirt bikes.

The sentence “When I get old, I’m going to water my plants, do yoga, and ride dirt bikes” has parallel structure because all the verbs are in the same simple present tense form. When one or two words in a list are in a different form, as in “doing yoga,” it throws off the balance of the list and makes it unclear what is being compared.

What is wrong with this sentence? He like to take his sweet time on his walk home.

Comma splice

Dangling modifier

Subject-verb agreement

Sentence fragment

The subject in this sentence is singular, while the verb is plural. They like, but he likes. Many people use the sound of constructions to decide whether or not they are correct. Often people do not fully grasp the rules of grammar until they are forced to memorize them for a foreign language and find out that there are similar rules in their native language.

Which sentence shows possession?

She pet the dog gingerly and said, “I love it’s smell.”

She pet the dog gingerly and said, “I love its smell.”

She pet the dog gingerly and said, “I love its’ smell.”

She pet the dog gingerly and said, “I love that smell.”

When using the word its to show possession, do not use an apostrophe. This is an endless source of confusion for students and of typos even for the learned. Blame it on autocorrect if you have to, but it’s better to get it right the first time.

Where do you need a comma in this sentence?

The caterpillars survived the heat but, they were no match for the wasps.

The caterpillars survived the heat but they were no match, for the wasps.

The caterpillars survived the heat, but they were no match for the wasps.

The caterpillars, survived the heat but they were no match for the wasps.

The comma needs to go directly before the conjunction “but.” This punctuation divides the two independent clauses from each other. An independent clause has a subject and a verb and communicates a complete thought. If you have have an indpendent clause and a dependent clause, you would not need a comma before the conjunction.

What is wrong with this sentence? She wondered how her absences would effect her grade.

Subject-verb agreement

Dangling modifier

Word choice

Comma splice

Wrong word choice makes this sentence incorrect. Effect and affect are often mixed up, for obvious reasons. These two are quite confusing, as they both can be nouns or verbs, with different meanings in conjunction with the different part of speech. Most people confuse them by using effect—which as a verb means “to bring about”—when they mean affect—which means to influence or produce a change.

Why do people often confuse there, they’re, and their?

They are homonyms, words that sound alike but have different meanings.

They are spelled the same.

They are synonyms with different meanings.

They do not know what they want to say.

The words they’re, there, and their sound the same, which makes them homonyms. Yet, even though they sound alike theirs a big difference between there meanings. It’s crucial for writers to get they’re meaning right if they don’t want to make a fool of themselves.

Which of the following has a split infinitive?

She warned me not to use split infinitives in my writing, but I didn’t know what that meant.

She warned me not to use split infinitives in my writing, but I didn’t know what not to do.

She warned me against using split infinitives in my writing, but I didn’t know what that meant.

She warned me to not use split infinitives in my writing, but I didn’t know what that meant.

An infinitive is the form of the verb with “to” in front of it. The infinitive is the verb’s basic form, which has not been conjugated yet to show who is doing the action. A split infinitive splits the “to” from the verb, breaking the basic verb form, as in “to not use.” Even though everyone understands what this means, it’s a big grammatical heresy.

Which sentence has a passive construction?

She was rowing a boat for three hours when the boat sprung a leak.

She was rowed in a boat for three hours when the boat sprung a leak.

She rowed for three hours before the boat sprung a leak.

The boat rowed along for three hours before it sprung a leak.

Passionate English teachers vehemently warn students against using the passive construction. The passive construction flips the action of the sentence so that the sentence structure focuses on to whom the action was done instead of who was doing the action. This creates a lack of clarity and precision, as in “She was rowed in the boat.” The sentence may be more direct if the person rowing were the subject of the sentence.

What is wrong with using “to be” verbs?

They are grammatically incorrect.

They do not conjugate into many verb tenses.

They do not communicate very specific actions.

They always create passive constructions.

Students often conflate the warning against using the passive voice and that against “to be” verbs. Doubtless, they are very similar, and “to be” verbs are used to create a passive voice. However, not all uses of “to be” are passive. The problem with them is a matter of style. Using the more general “to be” verbs means that you miss the opportunity to bring in much stronger active verbs to give nuance to what you are communicating.

Which choice correctly fills in the blank? To ____ did you write this check for $100,000, darling?

Who

Whom

Him

Them

While the old who/whom conundrum confuses droves of English users, it’s relatively easy to decide which one to use if you understand your parts of speech. “Who” is a pronoun which can be used as a subject, but it is never used as an indirect object. “Whom” only operates as an object of a verb or preposition. In this sentence, “whom” correctly fills in the blank to inquire about the mysterious recipient of 100 grand.

What is the grammatical error in this sentence? We went looking for deer, but all we found was an wild pig.

Incorrect article

Comma splice

Passive voice

Missing comma

This sentence contains an incorrect article. “A” should come before words beginning with consonants, while “an” should only come before words beginning with vowels. The reason for this is mainly aural; “an” breaks up the sounds between words so that we can hear a clear word break.

How do you decide whether to use “which” or “that”?

Depends how you feel

That comes after a comma, which with no comma

Which is usually used for non-essential clauses, that for essential clauses

That is usually used for non-essential clauses, which for essential clauses

While there is not a hard and fast rule for these words, the general rule of thumb is that "which" sets apart a non-essential phrase or clause, which is a phrase or clause that is not necessary for the sentence to retain its meaning. "That" is used for essential phrases or clauses that restrict the meaning of the sentence.

Which sentence is grammatically correct?

Than I thought to myself, I would rather be alone then be with this joker.

Then I thought to myself, I would rather be alone than be with this joker.

Then I thought to myself, I would rather be alone then be with this joker.

Than I thought to myself, I would rather be alone than be with this joker.

Then/than are often confused and misused, and they are sick of it. They want to be respected for who they really are. They want you to know that “then” properly refers to time, and “than” properly points to comparison. In this case, “then I thought” and “than be with.”

Which sentence demonstrates proper comma usage?

We wanted it to rain but not to flood.

We wanted it to rain, but not to flood.

We wanted it to rain, but did not want it to flood.

We wanted it to rain but we did not want it to flood.

The sentence “We wanted it to rain but not to flood” reflects proper comma usage. Even though it does not have a comma, it is not supposed to and therefore is correct. Since the first clause of the sentence is the only independent clause, the sentence does not need a comma before the conjunction to set off a dependent clause, which is a clause without a subject and a verb.

Which sentence correctly uses a semicolon?

I told him I would be wearing my camouflage; but I didn’t expect to be lost in the woods for days.

I told him I would be wearing my camouflage; I didn’t know they would never find me.

I told him I would be wearing my camouflage, but I didn’t expect to be lost in the woods; for days.

I told him I would be wearing; my camouflage, my fishing vest, and my red hat.

The most common use of the semicolon is to separate two independent clauses without a conjunction. The sentence “I told him I would be wearing my camouflage; I didn’t know they would never find me” accurately achieves this objective. Semicolons should be reserved for separating two independent clauses that are closely linked and merit being joined together.

Which sentence is in the subjunctive?

I would love to be a wizard.

I used to be a wizard, before I cut my hair.

If I were a wizard, I would use my power to turn all the corn into candy corn.

Wizards have had mysterious powers before the beginning of time.

The subjunctive is used to show that a situation is hypothetical rather than actual. One way to form the subjunctive is to use “were” instead of “was,” as in “If I were a wizard, I would use my power to turn all the corn into candy corn.” People often do not use the subjunctive properly in conversation, so it’s a good way to come out as a grammar nerd.

Which sentence properly uses the colon?

I need you to pick up: tofu, broccoli, bok choy, and water chestnuts, and then to make stir fry for me.

I need you to pick up tofu, broccoli, bok choy, and water chestnuts: and then to make stir fry for me.

I need you to pick up tofu, broccoli, bok choy, and water chestnuts: then make stir fry for me.

I need you to pick up the following: tofu, broccoli, bok choy, and water chestnuts, and then to make stir fry for me.

The colon should be used to signal that what follows will give more information about what came before, and it always follows a complete sentence. The only sentence above that does both of these correctly is “I need you to pick up the following: tofu, broccoli, bok choy, and water chestnuts, and then to make stir fry for me.”

Which sentence correctly punctuates a list?

This summer we are driving to Dallas, Texas, Memphis, Tennessee, St. Louis, Missouri, and Louisville, Kentucky.

This summer we are driving to Dallas, Texas; Memphis, Tennessee; St. Louis, Missouri; and Louisville, Kentucky.

This summer we are driving to Dallas; TX, Memphis; TN, St. Louis; Missouri, and Louisville; Kentucky.

This summer we are driving to Dallas Texas, Memphis Tennessee, St. Louis Missouri, and Louisville Kentucky.

A lesser-known and lesser-used function of the semicolon is its power to organize lists with multiple items nested within it. In this case, the semicolon helps to keep track of the list of cities and states among the larger list of places we will travel. When you need to separate multiple items in a list like this, use the comma to separate the items within the list and the semicolon to separate the greater distinctions.

What is wrong with this sentence? I guess we have less drinks than I thought we did.

It should be fewer instead of less.

Subject-verb agreement

Dangling modifier

It should be then instead of than

The words “fewer “and “less” often find themselves in the wrong place at the wrong time. Less refers to objects, while fewer refers to numbers, and they want to keep it that way. In this case, the sentence should read “I guess we have fewer drinks than I thought we did.”

Which sentence would you want to turn in to your English teacher?

I left you’re key under the stump.

I left you key under the stump.

I left your key under the stump.

I left key under the stump.

"You’re" and "your" can be so easily misunderstood, but it’s really easy to tell them apart. It’s like having good friends who are twins. You need to find the distinguishing freckle so you don’t embarrass yourself. In this case, it’s the apostrophe and the extra "e." When you see these marks, you should just know that you’re talking about a contraction of “you are” and not a possessive form of “you.”

What is the grammatical heresy in this sentence? I was ready to go party, I had finished all my work.

Incomplete sentence

Dangling modifier

Comma splice

Subject-verb agreement

A comma splice describes the error of separating two independent clauses with only a comma, as in the above sentence. This grave error can be amended by adding a conjunction before the comma or by using a semicolon instead of a comma.

Which sentence has no grammatical errors?

I was ready to go to the dance, which I had been looking forward to all year, but then I got gum in my hair.

I was ready to go to the dance which I had been looking forward to all year, but then I got gum in my hair.

I was ready to go to the dance, which I had been looking forward to all year but then I got gum in my hair.

I was ready to go to the dance, which I had been looking forward to all year: but then I got gum in my hair.

The sentence “I was ready to go to the dance, which I had been looking forward to all year, but then I got gum in my hair” correctly uses commas to set apart the nonessential clause, “which I had been looking forward to all year.” It also correctly uses a comma to separate the two independent clauses. Nonessential clauses are not necessary for the sentence to retain its meaning.

Where does this sentence need a comma? When she hears the thunder rumbling the dog cowers beneath the bed.

After when

After dog

Before the prepositional phrase

After the introductory clause

Introductory clauses, as in this sentence, are usually set apart with commas. The comma shows that this element of the sentence is not essential to the sentence’s meaning. Commas generally do not need to set apart a prepositional phrase, like “beneath the bed,” unless they come at the beginning of the sentence and are required for clarity.

What is the difference between a phrase and a clause?

A clause is a complete sentence.

A phrase is a complete sentence.

A phrase does not have a subject and verb, while a clause does.

A clause does not have a subject and verb, while a phrase does.

A phrase does not have both a subject and verb, while a clause does. Even with a subject and a verb, though, a clause is not necessarily a complete sentence. A dependent clause has a subject and a verb but does not express a complete thought. It leaves you hanging, as in this example: “When I get my check.”

Which choice correctly fills in the blank? This group ______ made me feel so welcome in this city.

Have

Has

Had

Will

Subject-verb agreement gets tricky when you’re dealing with a collective noun. Even though a “group” refers to a plural number of people here, the noun itself is singular. Since it is singular, it needs the singular verb “has” to agree with it.

What kind of sentence is this? After he stole the car, the man stopped at a gas station to get a slushy, and he got busted.

Simple

Run-on

Compound

Compound-complex

This sentence is compound-complex. Compound sentences unite two independent clauses, and complex sentences bring together a dependent clause with an independent clause. Compound-complex sentences join together both kinds.

About This Quiz

It’s possible that grammar is the most misunderstood element in our society. It gets such a bad rap as being a chore to learn in middle school and a burden to suffer through the rest of our lives. Images of teachers drilling the rules of diagramming come to mind, along with nightmares of writing the wrong part of speech on the board and turning to face a judging classroom.

But grammar geeks know that grammar is not just about being judged: it’s about judging others. Just kidding. Grammar is the glue that holds our language together. It’s the logic that provides sense for our thought constructions and allows us to communicate our ideas to others. A sophisticated understanding of the rules of grammar will enable you to communicate with greater nuance and precision. It gives you freedom from having to rely on someone else to fill in the blanks about your exact meaning. With a full set of grammatical tools, you can convey precisely what you mean.

Think about it. So many people use commas haphazardly, to show a ‘pause,’ as many have been taught. But the comma is rarely just about whether or not to pause. It shows the relationships among the elements of the sentence. How do you know whether or not to use commas to set off a dependent clause? It depends on whether the clause is crucial to the rest of the meaning of the sentence. How do you know whether to use a semi-colon or use a period and create a new sentence? The semi-colon indicates that the two independent clauses are closely connected.

Rather than being constrictive, grammar rules give us the freedom to communicate what we mean! Are you in control of what you say and write? Find out with this quiz!

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